Internal-combustion engine



F. AC KER'MANN.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED MAY 31, I918.

1 ,333;591 Patented Mar. 9, 1920.

3 SHEETSSHEET I.

fig. l. $241 abtozme 1 F. ACKERMANN'.

INTERNAL COMBUSTION ENGINE. APPLICATION FILED MAY3I, 1918.

1,333,591. Patented Mar. 9,1920.

3 SHEETS-SHEET 2.

F. ACKERMANN INTERNAL COMBUSTION. ENGINE. APPLICATION FILED MAY 31, 1918.

1,333,591. Patented Mar. 9, 1920.

3 SHEETS-SHEET 3.

avwwltoz fiedrzzilaicmwm FREDERICK ACKERMANN, OF OAK PARK, ILLINOIS.

INTERNAL-COMBUSTION ENGINE.

Specification of Letters Patent. i

Application filed May 31, 1918. Serial No. 237,601.

To all whom it may concern:

Be it known that I, FREDERICK AoKER- MANN, a citizen of. the United States, and a resident of Oak Park, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Internal-Combustion Engines, of which the following is a specification.

This invention has reference to an improvement in engines of the internal combustion type.

An object of this invention is to provide an engine structure wherein all the burnt gases are withdrawn from the combustion chamber, all back pressure is eliminated, power can be used to the end of the travel of the piston, the intake valve closes earlier than in present types of engines, greater compression may be obtained, a largercombustion chamber is provided, and wherein a lighter gas may be used as there is no burnt an internal combustion engine constructed according to the present invention, the section being taken through the engine near one side and showing the operating mechanism for controlling the secondary piston and the exhaust valve carried thereby, the secondary piston being disposed in its lowered position. i i

Fig. 2 is a similar View taken on a different plane through the engine and showing the intake valve and its mechanism.

Fig. 3 is a view similar to Fig. 1, showing the secondary or auxiliary piston raised.

Fig. 4 is a side elevatlon of the. engine, parts being broken away to show the valve operating mechanism.

Fig. 5 is a top plan view of the engine.

Fig. 6 is an enlarged transverse section through the engine taken on the line 66 of Fig. 2.

F ig. 7 is a detail enlarged side elevation of the secondary or auxiliary piston.

Fig. 8 is a diagrammatic view of the valve operating cams, showing the timing of operation thereof.

Referring to these drawings by numerals,

10 designates a crank case of any suitable construction and which supports the lower end of a cylinder 11. While the present drawings illustrate a single cylinder engine, it is, of course, understood that the engine may comprise any number of cylinders as the parts hereinafter described are merely duplicated for each cylinder.

- The crank case 10 houses a crank shaft 12 to which one end of a connecting rod 13 is secured, the other end of the connecting rod being pivoted to a'piston 14 of usual construction adapted to reciprocate in the cylinder 11. The upper part of the cylinder 11 is inclosed by a water jacket 15, and is provided at one side with a hollow projection 16 in which is formed an intake chamber 17 leading to the upper part of the cylinder 11 at a point spaced below the top wall thereof. An intake valve 18 is seated in the bottom of the intake chamber '17, and is carried on a, stem 19 which extends downward and diverges from the lower end of the cylinder 11. A spring 20 is carried by the rod 19 and bears against a bushing 21 fitted through the bottom of the projection 16 for normally seating the valve 18. A push rod 22 is slidably mounted in a sleeve bearing 23 carried upon the upper end of the crank case 10, the rod 22 projecting into the crank case and carrying a roller 24 adapted to ride upon a cam 25. The cam 25 has a lobe at one side adapted to lift the intake valve 16 upon the intake stroke of the piston 14.

An auxiliary or secondary piston 26, in the form of a disk, is mounted to reciprocate in the upper end of the cylinder 11 and when raised lies above the intake chamber 17. The piston 26, as shown in detail, in Fig. 7, has a hollow upstanding stem 27 slidably engaging through the head 28 of the cylinder, and has at the juncture of the stem with the piston 26 lateral orifices or ports 29 which open into a central port*-30 leading through the under side of the piston 26. The piston 26 carries an exhaust valve Patented Mar. 9, 1920.

31 which seats upwardly in the port 30, and has a stem 32 which is slidably mounted in the stem 27 of the piston. A spring 33 surrounds the rod 32 and is seated in the 1101 low stem 27 between a shoulder therein and a pin or the like on the rod The upper end of the hollow stem 27 has an outstanding annular flange 34 beneath which 1s d sposed a spring 35 housed at its lower end 1n the head 28 of the cylinder. The spring 35 normally urges the piston 26 upward and the spring 33 normally urges the exhaust valve 31 upward into closed positlon.

The head 28 of the cylinder is provided with an exhaust chamber 36 surroundlng the lower end of the hollow stem 27 and opening into an exhaust port 37 in one side of the head which may be controlled by a normally seated spring pressed valve 38.

The head 28 of the cylinder carriesa post 39 at one side which extends beyond the stem 27, and upon which are pivoted rocker arms 40 and 41. The rocker arm 40 is in the form of an open frame hearing at one end upon the annular flange 34 and at its other end is connected by pin and slot connection to a hollow push rod 42 which extends downward along one side of the engine and is slidably supported in the projection 16. An inner push rod .43 is mounted in the hollow rod 42 and is movable independently thereof through the same. The inner rod 43 has connection with the inner rocker arm 11 which lies within the rocker arm 40 as clearly shown in Fig. 5.

The cam 25 Which controls the operation of the intake valve is supported upon a cam shaft 44 carried within the casing 10 and adapted to turn at half the speed of the crank shaft 12. The shaft 44 is provided with a second cam 45 having an intermedi ate lobe 46 at one side and lateral lobes 47 spaced substantially 10 degrees behind the intermediate lobe 46, the latter having a cam surface of substantially the same radial height as that of the lobes 47 and extending through an arc of substantially ten degrees. The hollow rod 42 is provided upon its lower end with a pair of rollers 48 adapted to bear against the cams 47, and the inner rod 43 carries an anti-friction roller 49 adapted to ride on the cam 46.

In operation, the cams are so positioned upon the shaft 44 that upon the suction stroke of the piston 14 the piston 26 is raised to augment the suction and insure the complete expansion and evaporation of the hydrocarbon fed through the intake chamber 17. The upper piston 26 is maintained in a raised position duringthe power and compression strokes. Upon the exhaust stroke, however, the cam 46 first operates the inner push rod 43 and opens the exhaust valve 31, and immediately subsequent the cams 47 force the piston 26 downward while the valve 31 is maintained open. This downward movement of the piston 26 forms an upper compartment in the combustion chamber through which the burnt gases are forced by the main piston 14 as it rises. The two pistons 14 and 26 are brought into proximity with each other upon the completion of the exhaust stroke so that practically increases in a relatively great proportion to the stroke of the main piston and effects the suction in the combustion chamber from the very beginning of the intake stroke of the piston. A relatively large charge is therefore drawn into the engine, and the full effect of the power stroke is obtained as no burnt gases are left in the combustion chamber.

As the piston 26 rises, and as the valve 31 is closed at this time, the exhaust gases in the upper end of the cylinder 11 are forced out through the port 37 and past the valve 38. Thus, any back pressure in the exhaust can not be communicated to the combustion chamber as the valves are immediately closed and the upper piston 26 increases the tendency to create a vacuum as Well as immediately closing communication between the cylinder and the exhaust.

What is claimed is:

1. In an internal combustion engine, the

combination of a cylinder, a piston traveling in the cylinder, a second auxiliary piston also traveling in the cylinder and having an exhaust port and a valve seat therein, a valve carried by the auxiliary piston and arranged to move toward and from said seat, a hollow rod carrying the auxiliary piston and fitted to reciprocate in the cylinder, spring means engaging between the rod and cylinder to yieldingly raise the auxiliary piston, spring means within the hollow rod acting to keep the valve on its seat, a pivoted striker comprising an open rectangular frame adapted to come in contact with the rod for depressing the auxiliary piston, a second striker mounted on the same pivot with the first striker and operating-within the open rectangular frame constituting the first striker for engaging the valve stem and moving the valve off its seat, a tubular rod for actuating said first striker, a second rod within the tubular rod for actuating the second striker, and successively acting cams for moving said tubular and otherrod.

2. In an internal combustion engine, the combination of a cylinder having a piston therein, a second auxiliary piston in the cylinder having an exhaust port and a valve seat therein, a piston rod reciprocating in the cylinder and carrying said auxiliary piston, said rod having an out-turned flange on its upper end, a spring confined between the flange and cylinder for yielding lifting the piston rod, a VIlWi carried by the auxiliary piston, a valve stem connected to the valve and projecting up through the rod, a spring fitted in the rod and connected to the valve stem for yielding raising the valve, a striker composed of an open rectangular frame pivoted on the cylinder and arranged to en age the piston rod, a second striker rocking 21 out the same pivot with the first mentioned striker and operating in saidopen rectangular frame for engaging the valve stem, a tubular rod connected to the first striker, a rod Within the tubular rod for actuating the second striker, and cams for independently lifting said rods.

FREDERICK ACKERMANN. 

